EyeWorld is the official news magazine of the American Society of Cataract & Refractive Surgery.
Issue link: https://digital.eyeworld.org/i/227001
62 EW MEETING REPORTER Reporting live from the 9th International Symposium of Ophthalmology (ISO) in Guangzhou, China December 2013 Reporting live from the 9th International (ISO 2013) in Guangzhou November 9, 2013 New technologies shifting paradigms in cataract and glaucoma An overview of new techniques, technologies, and treatment concepts being developed at Bascom Palmer Eye Institute (BPEI, Miami) served as a snapshot of some of the hottest developments in ophthalmology today, as presented in one of the morning sessions on the first day of the 9th International Symposium of Ophthalmology (ISO) in Guangzhou. Certainly one of the most talked about new developments in ophthalmology in general and possibly the hottest topic in cataract surgery in particular today is femtosecond laser-assisted cataract surgery. William Culbertson IV, MD, U.S., said he has been interested in using femtosecond lasers to facilitate cataract surgery for 20 years now. As far as phacoemulsification has come over the years, he said, there remain a number of imperfections with the procedure, among them the repeatability of manual incisions, the centration of the capsulorhexis and subsequently of the IOL, and the consistency of relaxing incisions and refractive outcomes. Safety could also be improved, with current phaco technologies still susceptible to complications such as phaco burns and posterior capsule opacification. The femtosecond laser offers a promising solution to these imperfections. Perhaps most significantly, femtosecond lasers have the potential to render phacoemulsification obsolete: Lens fragmentation with the femtosecond laser significantly reduces ultrasound energy, particularly by reducing effective phaco time—a reduction of up to 99% with the Catalys (Abbott Medical Optics/OptiMedica). "The future is for ultimate elimination of ultrasound energy," said Dr. Culbertson— very good, he added, in terms of corneal health and inflammation. A similar paradigm shift may be in store for glaucoma surgeons in the near future. "You're not going to be doing trabeculectomy a few years from now," predicted Paul Palmberg, MD, U.S. The goals of glaucoma surgery, he said, should be to achieve and sustain a low intraocular pressure, avoid complications, and minimize inflammation. The ideal surgery should be efficient in terms of the performance of the procedure itself as well as in terms of postoperative care, and should minimize cost. Based on these criteria, neither the current standard of trabeculectomy nor the previously touted replacements—mainly large tube implants—are perfect: Valvelike trabeculectomy avoids early and late hypotony and has been shown to halt net visual field loss when a mean IOP of 11 mm Hg is achieved, but is difficult to perform; tubes, on the other hand, while often equal to or better than trabeculectomy in terms of efficacy, tend to need supplementary medication and are expensive and inefficient procedures. Tubes also introduce new complications such as corneal edema and motility disturbances. There are, however, a pair of new devices that Dr. Palmberg believes may eventually replace trabeculectomy. The AqueSys is a noodle-like drainage tube that works through ab-interno subconjunctival drainage. Combined with mitomycin-C (MMC), the device has been observed to maintain an IOP of 7-13 mm Hg. Meanwhile, the InnFocus MicroShunt is an implant made from SIBS, the same substance that has been used to coat heart stents for more than a decade. Also combined with MMC, the device achieves a mean IOP of 10 mm Hg, with no supplementary medication up to two years after implantation. At the moment, said Dr. Palmberg, trabeculectomy remains the standard, but only until these devices gather five-year data. At that point, he believes, "scleral dissection in glaucoma surgery will go the same way [it did] with cataract surgery." Editors' note: Dr. Culbertson has financial interests with Abbott Medical Optics. Cataract program kicks off with complicated cases The first cataract symposium of the 9th ISO in Guangzhou—the meeting's Academia Ophthalmologica Internationalis (AOI) Symposium— focused on complicated cases. Here, Charles McGhee, MD, New Zealand, delivered the first of 20 named lectures to be presented at the meeting. Dr. McGhee's lecture focused on cataract surgery in the context of weak or damaged lens zonules. A degree of lens zonule deficiency, he said, while not uncommon, is often unexpected. It should be anticipated in conditions such as pseudoexfoliation, Marfan syndrome and ocular trauma. Dr. McGhee detailed a number of phaco techniques and ancillary devices that enable better management of these cases. In addition, he emphasized preoperative planning and maximizing the safety of the technique to avoid complication. At the same symposium, Dennis Lam, MD, China, Congress president and scientific program chair of the meeting, delivered the Academia Lecture on "All you need to know about posterior capsule rupture." Dr. Lam described techniques such as bimanual anterior vitrectomy to manage complications of PCR such as extension of vitreous in the anterior chamber.